Tool for grooving or cutting pipes

ABSTRACT

A hand tool or grooving or cutting pipes has an aperture for receiving a portion of pipe, and adjustable support means. A cutting or grooving wheel is displaceable along a predetermined path to cause it to move radially relative to the pipe, as the tool is manually rotated round the pipe.

BACKGROUND OF THE INVENTION

The present invention relates to a tool for grooving or cutting pipes.It particularly relates to a hand tool capable of dealing with a rangeof pipe diameters.

International patent application WO86/03439 discloses a pipe cutterformed as a single cylinder having an entry slot. This device suffersfrom the disadvantage that it is not possible to make a quick, simpleand accurate adjustment for a different diameter of pipe.

SUMMARY OF THE INVENTION

It is an object of this invention to provide a new or improved tool forgrooving or cutting pipes which overcomes or reduces this disadvantage.

According to this invention, there is provided a tool for treating apipe, said tool comprising a body having an aperture for receiving aportion of a pipe to be treated, pipe support means displaceably mountedon the body so as to be displaceable to project into the aperture to avariable extent, and a pipe-treating wheel rotatably mounted on the bodyso that a pipe portion in the aperture is engageable between thepipe-treating wheel and the pipe support means, the pipe-treating wheelbeing displaceable along a predetermined path relative to the pipeportion such that its operative portion moves inwardly relative to thepipe portion, in which the tool further includes a rotatably mounted camarranged to adjust the position of the support means.

Thus, the cam may displace the pipe support means to allow differentpipes to be treated by the tool of this invention.

Preferably, the cam has a plurality of cam flats arranged at respectivepredetermined distances from its rotational axis.

Conveniently, the support means comprises two support rollers arrangedto define an isosceles triangle with the pipe-treating wheel when thepipe-treating wheel is at an intermediate location on its path, thesupport rollers being mounted on a block which is displaceable along theaxis of symmetry of the triangle.

Desirably, the operative portion of the pipe-treating wheel moves bothradially and circumferentially relative to the pipe portion, the pathbeing selected so that, when the tool is rotated relative to the pipe,the pipe-treating wheel is urged against the pipe to effect treatment.

Preferably, the path of the pipe-treating wheel is tangential to an arcof a circle whose centre lies at the centre of the tool.

Conveniently, the pipe-treating wheel is rotationally fixed with an axlepin which is rotatably located in an elongate slot which defines saidpredetermined path of displacement.

Said elongate slot may be a linear slot.

Alternatively, the body of the tool may be formed in two parts, one partcarrying the pipe-treating wheel and the other part carrying the pipesupport means, the two parts being hingedly connected together, and thetool further comprising a compression spring arranged to urge the twoparts of the tool together.

Preferably, the tool includes means for urging the pipe-treating wheelinwardly along said predetermined path. This is to urge it to contact apipe. When contact is established, rotation of the tool relative to thepipe urges the pipe-treating wheel against the pipe to effect treatment.

The pipe-treating wheel may be a form roller for forming a groove in thepipe or a cutting wheel for cutting the pipe.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will now be described in greater detail by way ofexample only, with reference to the accompanying drawings in which:

FIG. 1 is a perspective view of a pipe grooving or swaging tool;

FIG. 2 is an axial view of the tool, partly cut away, and showing adifferent external form;

FIG. 3 is a section view along the line III--III of FIG. 2 showing anadjustment arrangement which does not form part of this invention;

FIG. 4 is a scrap view of parts seen in FIG. 2, but to a larger scale;

FIG. 5 is an axial view of the tool partly cut away and showing anadjustable cam embodying the invention;

FIG. 6 is a side view of the cam shown in FIG. 5;

FIG. 7 is a side view of another embodiment; and

FIG. 8 is a side view of a further embodiment.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

A generally cylindrical metal body 10 is formed of two generallycylindrical portions 12, 14 secured together by screws 16. The body hasa central opening 18 extending axially from a front face 20 of oneportion 12, completely through that portion and part way through theother portion 14. The opening 18 also extends laterally to an opening 22in the composite cylindrical face 24. The mating faces of the portions12, 14 have recesses for housing further components. Thus there is apipe support assembly 26 comprising a spaced coplanar pair of supportrollers 28 rotatably mounted on a block 30. The block 30 is slideablymounted in a radially extending recess 32 so that it is displaceable inthe direction of a diameter of the body, about which the support rollers28 are symmetrical. There may be spring means (not shown) urging thesupport assembly 26 inwardly. There may be locking means (not shown),e.g. involving a locking pin passed through an aperture in the body 10to lock the support assembly in a desired radial position. In FIG. 3,there is shown an adjusting means which does not form part of thisarrangement for the support assembly 26 in the form of a screw 31.

FIGS. 5 and 6 show a support roller adjusting arrangement forming partof this invention. The support assembly 26 again comprises a spacedcoplanar pair of support rollers 28 and it is adjustably mounted on acam 46. The cam 46 is rotatably mounted on an axially extending pin 48and it is turned by means of an adjustable knurled knob 50 until thedesired cam flat on the cam 46 positions the pipe support assembly 26 inthe correct position for the pipe to be grooved. By this means thedistance between a pipe-treating wheel 38 and the pipe support assembly26 can be altered in order to receive pipes or tubes of varyingdiameter. The rotatable knurled knob 50 has markings thereon to show thediameter of the pipe which can be treated by the present invention. Asshown in FIG. 5 the cam 46 has a variety of cam flats to allow treatmentof pipe diameters ranging 15 mm, 16 mm, 18 mm, 19 mm, 20 mm and 22 mm.As will be realised, different cams may be used to extend the range ofpipes to be treated by the present invention.

On the other side of the central opening 18 from the support assembly26, there is a circumferentially extending recess 33 which has a deepercentral portion providing a cam slot 34. This defines a linearlyparallel sided slot which is formed along a line tangential to an arcstruck about the axis of the opening 18. The pipe-treating wheelcomprises a form roller 38 which is rotationally fast with a pivot pin40 engaged in the cam slot 34. Thus the pin 40 can roll along the camslot, with corresponding rotation of the form roller 38. A spring 42urges the form roller 38 away from the radially outer end of the camslot 34. The spring 42 is mounted in a recess 43 formed in the portion12 of the body 10 and bears against the pivot pin 40.

In use, the pipe support assembly 26 is adjusted to a positionappropriate to the pipe diameter by turning the knurled knob 50 to theappropriately indicated pipe diameter as shown in FIG. 5. An end portionof the pipe is then located in the tool. This can easily be done bypushing it in through the lateral opening 22. In the process, the pipeportion pushes the form wheel 38 to the radially outermost end of thecam slot. The spring 42 is thus urging the form roller 38 against thepipe. The pipe is pushed axially relative to the tool so that it abutsagainst the end face defining the central opening 18. (As shown in FIG.3 there may be a special abutment piece 44). The tool is then rotatedrelative to the pipe. As viewed in FIG. 2 or FIG. 5 the tool is turnedanticlockwise. (To assist this, it is provided with a suitable grippingsurface on the cylindrical face 24, e.g. knurled as shown in FIG. 1, orscalloped as shown in FIG. 2). Friction between the form roller 38 andthe pipe causes the roller to rotate, and to tend to move along the camslot 34 in a clockwise sense as seen in FIG. 2, so that it movesgradually radially inwardly. Rotation of the tool is continued forseveral complete rotations, until the pivot pin 40 of the form rollerhas reached the end of the slot 34. The form roller 38 is thenprojecting into the central opening 18 by a predetermined degree, andhas thus formed a groove of predetermined depth in the pipe portion.

For successful operation of the device, it is necessary for the path ofthe cam slot 34 to be suitable. If it comes radially inwardly toosteeply, the tool will not work, because the form roller 38 will biteinto the pipe and jam. But if the travel is too gradual, the form roller38 will simply skate over the surface of the pipe, without being forcedto travel along the path and form a groove in the pipe. The cam 46 maybe replaced by a larger cam in order to provide adjustability in therange 10-16 mm diameter of pipe.

If the central opening 18 does not extend fully through the body, thetool is suitable for providing pipes with grooves a standard distancefrom their ends. Of course, a tool as described can have a through-boreso that it can be located anywhere along the length of a pipe. This willgenerally be the case where the tool is arranged as a pipe cutting tool.A pipe cutting tool is constructed in the same way as the illustratedgrooving tool, but the pipe-treating wheel comprises a cutting wheel inplace of form roller 38.

The lateral opening 22 may also extend through the entire thickness ofthe tool. This gives the added advantage that it may be used to cut apipe where one or both ends are attached to existing fittings or areotherwise inaccessible.

In a further embodiment illustrated in FIG. 7, a cutting wheel 38 isrotatably mounted about its axis, its pin 40 being located in holes inthe body of the tool. Upon insertion of the pipe between the supportrollers 28 and the cutting wheel 38, the inherent stiffness of thematerial of which the body is made tends to urge the cutting wheel 38into close abutment with the pipe.

In a yet further embodiment shown in FIG. 8, the body of the tool isformed in two parts hinged at 60 about pin 62. There is provided astrong compression spring 64 for urging that part in which the cuttingwheel 38 is supported towards the pipe.

Various modifications may be made to the tool as described withoutdeparting from the invention.

The pipe grooving or cutting tool is described as being formed of metal.It may, of course, be manufactured from a plastics material by, forexample, injection moulding.

Furthermore, the abutment piece 44 may be made adjustable to readilyvary the location of the circumferential groove from the end of thepipe.

I claim:
 1. A tool for treating a pipe, said tool comprising:a bodyhaving an aperture for receiving a portion of the pipe to be treated,pipe support means displaceably mounted on the body so as to bedisplaceable to project into the aperture to a variable extent, apipetreating wheel rotatably mounted on the body so that the pipeportion in the aperture is engageable between the pipe-treating wheeland the pipe support means, the pipetreating wheel being displaceablealong a predetermined path relative to the pipe portion such that itsoperative portion moves inwardly relative to the pipe portion, and arotatably mounted cam arranged to adjust the position of the supportmeans.
 2. A tool as claimed in claim 1, wherein the cam has a pluralityof cam flats arranged at respective predetermined distances from arotational axis of the cam, wherein said cam controls the extent towhich the pipe support means projects into the aperture.
 3. A tool asclaimed in claim 1, in which the support means comprises two supportrollers arranged to define an isosceles triangle with the pipe-treatingwheel when the pipe-treating wheel is at an intermediate location on itspath, the support rollers being mounted on a block which is displaceablealong an axis of symmetry of the triangle.
 4. A tool as claimed in claim1, in which the operative portion of the pipe-treating wheel moves bothradially and circumferentially relative to the pipe portion, the pathbeing selected so that, when the tool is rotated relative to the pipe,the pipe-treating wheel is urged against the pipe to effect treatment.5. A tool as claimed in claim 4, in which the path of the pipe-treatingwheel is tangential to an arc of a circle whose centre lies at thecentre of the tool.
 6. A tool as claimed in claim 1, in which thepipetreating wheel is rotationally fixed with an axle pin which isrotatably located in an elongate slot which defines said predeterminedpath of displacement.
 7. A tool as claimed in claim 6, in which saidelongate slot is a linear slot.
 8. A tool as claimed in claim 1, inwhich the body of the tool is formed in two parts, one part carrying thepipe-treating wheel and the other part carrying the pipe support means,the two parts being hingedly connected together, and the tool furthercomprises a compression spring arranged to urge the two parts of thetool together.
 9. A tool as claimed in claim 1, in which the toolincludes means for urging the pipe-treating wheel inwardly along saidpredetermined path.
 10. A tool as claimed in claim 1, in which thepipetreating wheel comprises a form roller for forming a circumferentialgroove in the pipe.
 11. A tool as claimed in claim 1, in which thepipetreating wheel comprises a cutting wheel for cutting the pipe.
 12. Ahand-powered tool for treating a pipe, said tool comprising:a bodyhaving an aperture for receiving a portion of the pipe to be treated,pipe support means displaceably mounted on the body so as to bedisplaceable to project into the aperture to a variable extent, apipetreating wheel rotatably mounted on the body so that the pipeportion in the aperture is engageable between the pipe-treating wheeland the pipe support means, the pipetreating wheel being displaceablealong a predetermined path relative to the pipe portion such that itsoperative portion moves inwardly relative to the pipe portion, arotatably mounted cam arranged to adjust the position of the supportmeans, and a manually operable knob, the cam being rotatable by means ofthe knob between a plurality of predetermined rotary positions at eachof which the tool is correctly set for treating a pipe of a particulardiameter.
 13. A tool as claimed in claim 12, wherein the cam has aplurality of cam flats arranged at respective predetermined distancesfrom a rotational axis of the cam, wherein said cam controls the extentto which the pipe support means projects into the aperture.
 14. A toolas claimed in claim 12, in which the support means comprises two supportrollers arranged to define an isosceles triangle with the pipe-treatingwheel when the pipe-treating wheel is at an intermediate location on itspath, the support rollers being mounted on a block which is displaceablealong an axis of symmetry of the triangle.
 15. A tool as claimed inclaim 12, in which the operative portion of the pipe-treating wheelmoves both radially and circumferentially relative to the pipe portion,the path being selected so that, when the tool is rotated relative tothe pipe, the pipe-treating wheel is urged against the pipe to effecttreatment.
 16. A tool as claimed in claim 15, in which the path of thepipe-treating wheel is tangential to an arc of a circle whose centrelies at the centre of the tool.
 17. A tool as claimed in claim 12, inwhich the pipetreating wheel is rotationally fixed with an axle pinwhich is rotatably located in an elongate slot which defines saidpredetermined path of displacement.
 18. A tool as claimed in claim 17,in which said elongate slot is a linear slot.
 19. A tool as claimed inclaim 12, in which the body of the tool is formed in two parts, one partcarrying the pipe-treating wheel and the other part carrying the pipesupport means, the two parts being hingedly connected together, and thetool further comprises a compression spring arranged to urge the twoparts of the tool together.
 20. A tool as claimed in claim 12, in whichthe tool includes means for urging the pipe-treating wheel inwardlyalong said predetermined path.